CSA Global, Principal Geologist, Dr Travis Murphy will present on “Development in Understanding of the Tritton-Girilambone Cu District, Lachlan Fold Belt, Australia; Resolving Hydrothermal Mineralisation in Multiply-deformed Rocks” at the upcoming PACRIM 2019 between 2-5 April 2019 in Auckland, New Zealand.
AusIMM’s PACRIM Congress brings together exploration, research, mining and project development professionals to review the geology, exploration and development of mineral deposits of the ‘Pacific Rim’. In 2019, PACRIM will have an integral focus on leading edge exploration technology, newly developed concepts regarding ore genesis and discovery, and development case studies.
The conference will demonstrate the most recent advances in academic research and geological understanding, regional surveys by government agencies and the industry’s latest discoveries and projects that showcase the importance of the Pacific Rim for global mineral wealth and investment and will features over 80 technical papers, presented by renowned industry leaders including 19 keynote speakers and 11 invited speakers.
The presentations will provide delegates with an update on research in mineral exploration and techniques, mineralisation styles and discovery case studies.
CONGRESS THEMES
Mineral system understanding
Mineral system and exploration targeting; Mineralisation Processes; Multi-scale characterisation: atoms to cratons; Geometallurgy of PACRIM deposits; and Data in Geoscience.
Exploration, Mining Investment and New Project Developments
Advances in exploration techniques; and Mining Investment and New Project Developments.
Mineralisation Styles
Epithermal Systems; IOCG and related deposits; Magmatic Fe-Ti-Cr oxide and Ni-Cu-PGE sulphide deposits; Orogenic Au; Intrusion-related Au; Porphyry Deposits; Skarn and Replacement Deposits; VMS/SEDEX and modern ocean floor systems; and Sediment hosted/Carlin deposits.
Provinces and Case Studies
China, Malaysia, Vietnam and Laos; New Zealand and Eastern Australia; PNG, Indonesia, Philippines; Chile and South America; and Northern Pacific Rim (North America and Russia).
ABSTRACT
The Tritton-Girilambone copper (+gold) district hosts the Tritton and Murrawombie mines, completed mines at Larsen’s and North-East, and undeveloped deposits at Avoca Tank, Budgery, Budgerygar, and Kurrajong. The total contained copper metal in the combined deposits is more than 750,000t; and exploration prospectivity remains significant.
Host-rocks to copper mineralisation are Ordovician in age and these rocks have been deformed during the Benambran and younger deformation episodes, resulting in complex overprinting relationships. Despite this, a consistent structural history, derived from recognised ductile deformation features, has been established across the Tritton-Girilambone district. Hydrothermal activity, manifest as alteration and sulfide mineralisation, occupies a discrete period within the structural history.
The prospective stratigraphy comprises a package of psammitic rocks enclosed within pelite/schist. Rheological contrast focusses development of discontinuities at contacts, and, in places, these are mineralised where intersected by younger deformation features. Four discrete fold generations and three associated cleavage/foliation fabrics are recognised, with relative timing established through observation of overprinting relationships. Importantly, the oldest cleavage, both pervasive and penetrative and associated with Benambran-age folding; is overprinted by disseminated pyrite in silica-pyrite ‘veins’ and as layer replacement. Pyrite is therefore introduced during younger deformation and overprinted by chalcopyrite mineralisation in the ductile to brittle transition. Mine-scale distribution of pyrite and chalcopyrite is consistent with structural orientations.
The amount of surface outcrop is poor, and as such, the deposit geology and controls on mineralisation are resolved through geological/structural mapping of underground exposure and solution-focussed campaign logging of diamond-core. Despite other interpretations of volcanic-associated sulfide mineralisation, exploration for these deposits has not been model-centric and relies heavily on associated geophysical (EM, IP, Magnetics) anomalism. A range of mineralisation textures and tenor can occur, with varying geophysical properties. It is therefore critical to utilise multiple geophysical techniques coupled with understanding of the litho-structural architecture to drive discovery.
ABOUT DR TRAVIS MURPHY
Dr Murphy is a geologist with more than 22 years’ experience across multiple sectors of the resource industry; including exploration, mine operations, planning, and production; as well as technical research roles. He has proven leadership skills and successes in exploration (lead team to discovery), mining (mine-geology as well as broader application of geoscience solutions to mining and minerals processing), and applied research (project lead in significant DNRM-GSQ funded Cloncurry Cu-Au prospectivity analysis; and key role in applied, industry-funded research into geological drivers of mass-mining (caving) methods). He specialises in structural geology, exploration and mine geology, and targeted geometallurgy/deposit-knowledge; and holds an Honorary Senior Fellow appointment at UQ-Sustainable Minerals Institute.
To connect with Dr Murphy, click here
